Commit ac10be5c authored by Rob Herring's avatar Rob Herring
Browse files

arm64: Use common of_kexec_alloc_and_setup_fdt() 



The code for setting up the /chosen node in the device tree
and updating the memory reservation for the next kernel has been
moved to of_kexec_alloc_and_setup_fdt() defined in "drivers/of/kexec.c".

Use the common of_kexec_alloc_and_setup_fdt() to setup the device tree
and update the memory reservation for kexec for arm64.

Signed-off-by: default avatarRob Herring <robh@kernel.org>
Signed-off-by: default avatarLakshmi Ramasubramanian <nramas@linux.microsoft.com>
Reviewed-by: default avatarThiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: default avatarRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210221174930.27324-7-nramas@linux.microsoft.com
parent b30be4dc

arch/arm64/kernel/machine_kexec_file.c

+8 −174
Original line number Diff line number Diff line
@@ -15,23 +15,12 @@ 
#include <linux/kexec.h>

#include <linux/libfdt.h>

#include <linux/memblock.h>

#include <linux/of.h>

#include <linux/of_fdt.h>

#include <linux/random.h>

#include <linux/slab.h>

#include <linux/string.h>

#include <linux/types.h>

#include <linux/vmalloc.h>

#include <asm/byteorder.h>



/* relevant device tree properties */

#define FDT_PROP_KEXEC_ELFHDR	"linux,elfcorehdr"

#define FDT_PROP_MEM_RANGE	"linux,usable-memory-range"

#define FDT_PROP_INITRD_START	"linux,initrd-start"

#define FDT_PROP_INITRD_END	"linux,initrd-end"

#define FDT_PROP_BOOTARGS	"bootargs"

#define FDT_PROP_KASLR_SEED	"kaslr-seed"

#define FDT_PROP_RNG_SEED	"rng-seed"

#define RNG_SEED_SIZE		128



const struct kexec_file_ops * const kexec_file_loaders[] = {

	&kexec_image_ops,
@@ -40,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = { 


int arch_kimage_file_post_load_cleanup(struct kimage *image)

{

	vfree(image->arch.dtb);

	kvfree(image->arch.dtb);

	image->arch.dtb = NULL;



	vfree(image->elf_headers);
@@ -50,164 +39,6 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image) 
	return kexec_image_post_load_cleanup_default(image);

}



static int setup_dtb(struct kimage *image,

		     unsigned long initrd_load_addr, unsigned long initrd_len,

		     char *cmdline, void *dtb)

{

	int off, ret;



	ret = fdt_path_offset(dtb, "/chosen");

	if (ret < 0)

		goto out;



	off = ret;



	ret = fdt_delprop(dtb, off, FDT_PROP_KEXEC_ELFHDR);

	if (ret && ret != -FDT_ERR_NOTFOUND)

		goto out;

	ret = fdt_delprop(dtb, off, FDT_PROP_MEM_RANGE);

	if (ret && ret != -FDT_ERR_NOTFOUND)

		goto out;



	if (image->type == KEXEC_TYPE_CRASH) {

		/* add linux,elfcorehdr */

		ret = fdt_appendprop_addrrange(dtb, 0, off,

				FDT_PROP_KEXEC_ELFHDR,

				image->elf_load_addr,

				image->elf_headers_sz);

		if (ret)

			return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);



		/* add linux,usable-memory-range */

		ret = fdt_appendprop_addrrange(dtb, 0, off,

				FDT_PROP_MEM_RANGE,

				crashk_res.start,

				crashk_res.end - crashk_res.start + 1);

		if (ret)

			return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);

	}



	/* add bootargs */

	if (cmdline) {

		ret = fdt_setprop_string(dtb, off, FDT_PROP_BOOTARGS, cmdline);

		if (ret)

			goto out;

	} else {

		ret = fdt_delprop(dtb, off, FDT_PROP_BOOTARGS);

		if (ret && (ret != -FDT_ERR_NOTFOUND))

			goto out;

	}



	/* add initrd-* */

	if (initrd_load_addr) {

		ret = fdt_setprop_u64(dtb, off, FDT_PROP_INITRD_START,

				      initrd_load_addr);

		if (ret)

			goto out;



		ret = fdt_setprop_u64(dtb, off, FDT_PROP_INITRD_END,

				      initrd_load_addr + initrd_len);

		if (ret)

			goto out;

	} else {

		ret = fdt_delprop(dtb, off, FDT_PROP_INITRD_START);

		if (ret && (ret != -FDT_ERR_NOTFOUND))

			goto out;



		ret = fdt_delprop(dtb, off, FDT_PROP_INITRD_END);

		if (ret && (ret != -FDT_ERR_NOTFOUND))

			goto out;

	}



	/* add kaslr-seed */

	ret = fdt_delprop(dtb, off, FDT_PROP_KASLR_SEED);

	if (ret == -FDT_ERR_NOTFOUND)

		ret = 0;

	else if (ret)

		goto out;



	if (rng_is_initialized()) {

		u64 seed = get_random_u64();

		ret = fdt_setprop_u64(dtb, off, FDT_PROP_KASLR_SEED, seed);

		if (ret)

			goto out;

	} else {

		pr_notice("RNG is not initialised: omitting \"%s\" property\n",

				FDT_PROP_KASLR_SEED);

	}



	/* add rng-seed */

	if (rng_is_initialized()) {

		void *rng_seed;

		ret = fdt_setprop_placeholder(dtb, off, FDT_PROP_RNG_SEED,

				RNG_SEED_SIZE, &rng_seed);

		if (ret)

			goto out;

		get_random_bytes(rng_seed, RNG_SEED_SIZE);

	} else {

		pr_notice("RNG is not initialised: omitting \"%s\" property\n",

				FDT_PROP_RNG_SEED);

	}



out:

	if (ret)

		return (ret == -FDT_ERR_NOSPACE) ? -ENOMEM : -EINVAL;



	return 0;

}



/*

 * More space needed so that we can add initrd, bootargs, kaslr-seed,

 * rng-seed, userable-memory-range and elfcorehdr.

 */

#define DTB_EXTRA_SPACE 0x1000



static int create_dtb(struct kimage *image,

		      unsigned long initrd_load_addr, unsigned long initrd_len,

		      char *cmdline, void **dtb)

{

	void *buf;

	size_t buf_size;

	size_t cmdline_len;

	int ret;



	cmdline_len = cmdline ? strlen(cmdline) : 0;

	buf_size = fdt_totalsize(initial_boot_params)

			+ cmdline_len + DTB_EXTRA_SPACE;



	for (;;) {

		buf = vmalloc(buf_size);

		if (!buf)

			return -ENOMEM;



		/* duplicate a device tree blob */

		ret = fdt_open_into(initial_boot_params, buf, buf_size);

		if (ret) {

			vfree(buf);

			return -EINVAL;

		}



		ret = setup_dtb(image, initrd_load_addr, initrd_len,

				cmdline, buf);

		if (ret) {

			vfree(buf);

			if (ret == -ENOMEM) {

				/* unlikely, but just in case */

				buf_size += DTB_EXTRA_SPACE;

				continue;

			} else {

				return ret;

			}

		}



		/* trim it */

		fdt_pack(buf);

		*dtb = buf;



		return 0;

	}

}



static int prepare_elf_headers(void **addr, unsigned long *sz)

{

	struct crash_mem *cmem;
@@ -314,12 +145,15 @@ int load_other_segments(struct kimage *image, 
	}



	/* load dtb */

	ret = create_dtb(image, initrd_load_addr, initrd_len, cmdline, &dtb);

	if (ret) {

	dtb = of_kexec_alloc_and_setup_fdt(image, initrd_load_addr,

					   initrd_len, cmdline, 0);

	if (!dtb) {

		pr_err("Preparing for new dtb failed\n");

		goto out_err;

	}



	/* trim it */

	fdt_pack(dtb);

	dtb_len = fdt_totalsize(dtb);

	kbuf.buffer = dtb;

	kbuf.bufsz = dtb_len;
@@ -343,6 +177,6 @@ int load_other_segments(struct kimage *image, 


out_err:

	image->nr_segments = orig_segments;

	vfree(dtb);

	kvfree(dtb);

	return ret;

}